The present invention relates to the game of golf. More specifically, the present invention relates to golf swing and training aids.
Golf courses generally have 18 holes spread over a landscaped area that customarily includes a number of hazards-water, rough, sand traps (also known as bunkers), and trees-that are designed to make the game more difficult. Difficulty is also increased by the varying distances among holes. Play on each hole is begun at the tee area, from which players "tee off" and "drive" the ball into the fairway or onto the green. At the end of the hole-which can vary in length from about 100 to 600 yards-is the putting green, which surrounds the actual hole, or "cup" into which the ball must usually be putted to complete the hole. Saint Andrews in Scotland, Augusta National in Georgia (site of the annual Masters tournament) and Pebble Beach in California have some of the most famous and difficult courses.
It is recognized that repetitive practice is essential to improving a golfer's game. In part, the repetitive practice is necessary to develop consistent swings for each of the clubs used on the course. A golfer who has established good habits and swing patterns for each club will post better scores in play, despite the varying conditions and hazards encountered on different courses.
This need for consistent practice to develop a consistent swing pattern is important for all clubs, but is most apparent for the putter. In the putting segment of the game of golf, the objective is to direct the ball across the putting green until it comes to rest in the hole or cup. The putting green is a smooth and closely cut grassy area surrounding the hole. An accurately hit golf ball will travel along a path to the hole. In the case where the path between the ball and hole contains a slope to one side or the other, the golfer will try to determine the proper target direction which will allow the ball (once struck) to follow a curved path to the hole.
Although the putting green is usually conditioned to provide an optimum surface over which to putt, a golfer's inability to accurately and consistently aim the ball and smoothly swing the putter can be a major source of undesirable "strokes" on the golfer's scorecard. When putting, it is very important that the face of the putter be placed at exactly a right angle in line to the target direction at the moment when the putter impacts the ball. Alignment of the putter adjacent to the ball in this manner is difficult when the ball rests even a short distance from the hole, since the golfer is usually unable to see the ball, club head, and target simultaneously. This problem also exists when using other types of golf clubs.
In general, a golfer attempts to ensure that the club head alignment and motion are co-linear with the intended direction at the exact point of impact with the ball. Ideally, the club head is maintained in alignment with the ball throughout the golfer's backstroke. This correct stroke will be referred to herein as a "pendulum swing". An example of a correct pendulum swing is shown in FIG. 2B, where a club head 32 is aligned to strike a ball 36 along a target path 50. During each position of proper pendulum swing, club head 32 is consistently aligned square with ball 36. A golfer capable of consistently repeating this stroke will putt the ball with more consistency and accuracy. Golfers who have not mastered pendulum swings tend to hit the ball with less consistency and accuracy. An example of an improper swing is shown in FIG. 2A, where club head 32 is shown during a backstroke. In this swing, the golfer brings club head 32 to the ball in an arc 52. At the point of impact with the ball, club head 32 may impart some spin to the ball, or may otherwise direct the ball off of the intended target line. It is desirable to provide a device and method which will permit a golfer to perfect the pendulum swing, thereby improving the golfer's score and satisfaction.
Part of the appeal of the game of golf is the difficulty of mastering these strokes. Weekend golfers, who do not have the luxury of constant practice, have a difficult time consistently putting the ball accurately. Consistency can only be achieved by constant and repeated training so that the golfer can replicate the correct club head alignment and motion as needed during play. A number of patents have attempted to provide improvements in a golf club that would help a golfer achieve consistency in club head alignment and motion.
One beneficial approach is shown in U.S. Pat. No. 5,640,777 to Densberger et al., commonly assigned with the present application, which is incorporated herein for all purposes. This patent shows a parallax correction device to ensure a golfer's head is properly positioned above a ball in putting. Another beneficial training device is shown in U.S. Patent Application Ser. No. 08/879,339, entitled "Detachable Training System for Golf Clubs" filed on Jun. 20, 1997, commonly assigned with the present application, which is incorporated herein for all purposes.
U.S. Pat. Nos. 5,388,831, and 5,207,429, to Quadri et al., and Walmsley et al, respectively, describe golf clubs which have light sources directly attached to the club shaft for aligning a club head with a ball. While these devices allow a golfer to align a club head along a target path, they do not help a golfer develop a correct pendulum swing. Because the light sources are directly coupled to the golf club, the golfer may still improperly swing. For example, the golfer is still able to improperly arc his swing as shown in FIG. 2A. Although an attached source can provide a good pointing reference to the golfer, such a configuration does not provide any positional reference to assist a golfer in developing a proper swing. Further, the light source attached to the club shaft changes the swing weight and feel of the club so that the golfer needs to readjust his swing when the laser source is removed. This reduces any beneficial training effect which may have been provided by the device.
There remains, therefore, a need for a training device and method which permits a golfer to develop a consistent stroke and pendulum swing. Preferably, the device should be portable and capable of being used indoors or outdoors to allow a golfer to practice the stroke in a variety of areas. The device and method should be capable of use without adding any attachments and undesirable weight to clubs a golfer would use in actual play.